Everyone deals with tomato troubles now and then. Here are the most common and frustrating ones:

Tomato hornworm: Follow the missing leaves until you find a huge, green caterpillar, plump after a diet of tomato leaves. Handpick them, toss them in the trash or leave them out for the birds. You can also use a spray that contains Bacillus thuringiensis, but the hornworm has to eat leaves sprayed with Bt before it can die.

Blossom end rot: The blossom end of the tomato turns brown and soft. It's caused by an imbalance or lack of calcium and watering too much or erratically. The problem is worse early in the season when temperatures swing widely. Once summer settles in, the problem goes away. Cut away the affected part of the tomato off and eat the rest.

Wilt: Suddenly all or part of the plant turns brown and dies. You've got wilt. Remove the affected part. Choose resistant varieties next year (look at the label). Many heirloom varieties are susceptible to wilt. Lots of compost in the soil helps plants stay strong.

Scald: Late in the season the tomatoes look white and scalded. They are. It's too much sun and not enough leaf cover to protect the fruit. Put a piece of shade cloth over the plant. Problem solved.

Nematodes: These are microscopic, eel-like worms that live in the soil. Some are beneficial, but many are not. They feed on plant roots. Symptoms include browning leaves, poor health and reduced yields. Solarize the soil to kill nematodes. Plant resistant varieties (check labels). Add lots of compost to the soil. French marigolds deter nematodes, but you have to plant the entire bed with them, then turn them under just as they bloom.

JULY CHECKLIST

• Don't worry if squash and melons wilt during the hottest part of the day as long as they recover each evening. If they don't recover, they aren't getting enough water.

• Plant a second crop of squash and beans to extend the harvest into fall. Cover newly planted seedlings with shade cloth or newspaper during the hottest part of the day until they are established.

• Trim spent flowers from crepe myrtles, black-eyed Susan, coneflowers, roses and agapanthus. Cut spent flower stalks of watsonia, daylilies, kniphofia and agapanthus.

• Order bulbs for the best selection: lilies, daffodils, hyacinths, tulips, crocus.

• Cut iris leaves to about three inches. Dig up rhizomes if crowded and replant.

• Beware people smoking around tomato plants. They can spread tobacco mosaic. If you smoke, wash your hands before handling tomato plants.

• Pick vegetables – especially zucchini – daily to keep plants producing.

• Add fresh water to birdbaths at least every other day.

• High temperatures are here to stay: Adding mulch helps conserve moisture and keep soil from baking and drying. Spread 2 to 4 inches of mulch over the entire garden. Remember to keep it a couple inches away from tree trunks and shrubs and plant stems.

• Check potted plants when temperatures exceed 100 degrees. They may need watering more than once a day. When watering, water gently until water comes out the bottom, and then water again.

• Cut Mexican evening primrose to the ground when flowers are finished and you'll get another flush of bloom in September.

• Remove flowers from basil plants to keep them producing leaves.

• Continue deep watering fruit trees through summer.

• Plants not to trim after July: rhododendron, camellia, dogwoods, deciduous magnolias. If you trim them now, you'll be cutting away next year's flower buds.

• Fruit trees can be summer pruned now. At this time of year they won't respond with lots of wild growth.

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